Apparatus for knitting loop fabric



Nov. 11 1969 v. J. LOMBARDI I 3,477,255

APPARATUS FOR KNITTING LOOP FABRIC Filed Aug. 24, 1967 4 Sheets-Sheet 1 INVENTOR. AcToR J'- LoMaA m Nov. 11; 1969 v. J. LOMBARDI 3,477,255

APPARATUS FOR KNITTING L'OOP FABRIC A Filed Aug. 24, 1967 4 Sheets-Sheet INVENTOR. \Acron J. LOMBARD\ Nov. 11, 1969 v. J. LOMBARDI 3,477,255

APPARATUS FOR KNITTING LOOP FABRIC Filed Aug. 24, 1967 v 4 Sheets-Sheet 3 I INVENTOR. \ACTOR Y Lomamam Nov. 11, 1969 v. JILO MBARDI APPARATUS FOR KNITTING LOOP FABRIC Filed Aug, 24, 1967' 4 Sheets-Sheet 4 3-H LOOP INVENTOR.

'mcToR S- LoMBARm Man,

United States Patent US. CI. 66-91 11 Claims ABSTRACT OF THE DISCLOSURE A circular knitting machine is provided with horizontally disposed needles and vertically disposed pattern jacks for knitting a loop fabric. The pattern jacks may be selectively operable to at least three vertical positions for producing multi-level loops in the knitted fabric. The pattern jacks include novel configurations at their upper terminal ends for forming multi-level loop fabric, or alternatively, a more uniform single level loop fabric. With the apparatus of this invention, random or pattern effects can be dictated in a knitted loop fabric, and the machine of this invention forms all loops on an outside surface of a tubular knit fabric.

BRIEF SUMMARY AND BACKGROUND OF INVENTION This invention relates to the knitting of loop fabrics, and in particular, the invention is concerned with an improved circular knitting machine for knitting loop fabrics. The improved machine of this invention may be used for knitting multi-level loops with patterned or random effects on a fabric, or alternatively, means may be provided for knitting a single level loop fabric having improved characteristics of uniform loop configuration and tightness.

It is known in the prior art to knit loop fabrics on circular knitting machines by the use of needles and sinkers. In one known prior art apparatus, loop forming elements such as sinkers are disposed horizontally on a dial member mounted outwardly of the cylinder, and needles are moved up and down about a cylinder to cooperate with the sinkers in forming knitted loop fabric from two yarns being fed to the machine.

In another known prior art apparatus loop-forming elements such as dial jacks are disposed horizontally on a dial member mounted inwardly of the cylinder, and vertically actuated cylinder needles cooperate with the horizontally actuated dial elements in forming knitted loop fabric from two yarns being fed to the machine. However, such prior art arrangements have been limited to forming all loops in the fabric to a single level at a single yarn-feeding station, or alternatively, single-level loops in combination with an absence of loops at a single yarn-feeding station. Additionally, such prior art apparatus forms loops on an interior surface of a tubular fabric knitted with a circular knitting machine, and it has been difi'icult to inspect the loop-forming operation during the knitting of a fabric. In fact, it has been necessary to turn the knitted fabric inside out before an adequate inspection can be made prior to any subsequent processing of the fabric.

The present invention provides for an improved knitting machine which knits a tubular fabric having loop formations on an outside surface of the tubular fabric. More importantly, the knitting machine of this invention can be operated to selectively control at a single yarnfeeding station the levels of loop formations on a knitted loop fabric during the knitting operation. In a preferred embodiment, the circular knitting machine of this invention is provided with horizontally disposed and operable needles which are associated with a dial and a "ice dial cam construction. In addition, novel pattern jack means are vertically disposed around a cylinder, and the pattern jack means are of a special configuration to form loops in a fabric which is being knitted. Each pattern jack means comprises an elongate jack member having an uppermost end which serves as a yarn engaging portion for forming loops in a fabric which is being knitted by a cooperation of the pattern jack means with the horizontally disposed needles. The yarn engaging portion of each pattern jack may include several levels of yarn engaging surfaces for dictating various sizes of loops. In one embodiment of a pattern jack construction, various levels of yarn engaging surfaces progress from a low loop-forming surface to a relatively high loop-forming surface, and the progression of the yarn engaging surfaces may be in increments or steps whereby each dictates a given loop size. In another embodiment of a pattern jack construction, the uppermost end of the jack is provided with a yarn engaging surface which is intended to initially form a loop configuration and then to expand the loop slightly to a uniform extent by a withdrawal of the pattern jack from the loop during the knitting process. Thus, the pattern jack means provided by this invention may be used to form at a single yarnfeeding station multi-level loop fabrics and also more uniformly controlled single-level loops in a fabric.

A pattern wheel is associated with the cylinder and pattern jack members for selectively dictating the vertical movement of individual pattern jacks. The pattern wheel is of the. type which includes means for engaging butts associated with the pattern jacks whereby the butts and therefore the jacks are actuated to any one of several levels. In a preferred arrangement, the pattern wheel includes means at a single yarn-feeding station for controlling the vertical movements of pattern jacks to three positions relative to a horizontal plane in which the knitting needle elements are operating.

The fabrics producible by the improved apparatus of this invention can be advantageously used for numerous purposes. For example, they may be left in loop form of single or multi-level, may be sheared, or random-sheared to provide novel effects in fabrics used in wearing apparel and elsewhere. Also, the multi-level loop construction which is provided by this invention is useful as a surgical fabric having improved properties. Such a fabric is described in greater detail in my copending application entitled, Improved Surgical Product for Dressing and Treating Wounds, and Method of Manufacture, Ser. No. 659,697 filed Aug. 10, 1967. Also, the apparatus of this invention can be used to produce a single-level loop fabric having greater uniformity of loop size and loop tightness than has been possible with prior art apparatus. Furthermore, the apparatus of this invention can be advantageously employed to produce separate and distinct fabrics each of a. different loop level without replacement of the loop-forming elements simply by selecting all the pattern jacks to a single level relative to the horizontal plane in which the knitting needle elements are operative.

These and additional features and advantages of the present invention will be discussed in greater detail below. In the detailed discussion reference will be made to the accompanying drawings, as follows:

BRIEF DESCRIPTION OF DRAWINGS FIGURES 1a through 10 illustrate a section of a prior art sinker and dial circular knitting machine for producing loop fabric;

FIGURES 2a through 2e illustrate a section of a prior art circular knitting machine for producing a pattern of loop configurations with a sinker and dial construction;

FIGURE 3 illustrates a vertical sectional view of an improved machine in accordance with the present invention, showing horizontally disposed needle means and vertically disposed pattern jack means for knitting a tubular loop fabric having loops on an outside surface of the fabric;

FIGURE 4 illustrates portions of the improved apparatus of this invention to show relationships between novel pattern jack means and a pattern wheel which dictates vertical movements of the loop-forming pattern jack means;

FIGURE 5 is a view similar to FIGURE 3, illustrating a pattern jack means lifted to a low-level loop-forming position;

FIGURE 6 is a view similar to FIGURES 3 and 5, showing a pattern jack means lifted to a high-level loopfor-ming position;

FIGURE 7 is a vertical sectional view of the improved apparatus of this invention, showing an alternative form of pattern jack means which may be used for controlling uniformity and tightness of loop configurations; and

FIGURE 8 is an illustrative example of a pattern which may be formed in a loop fabric in accordance with the teachings of the present invention.

DETAILED DESCRIPTION OF INVENTION Referring to FIGURES 1 and 2, prior art constructions of circular knitting machines are illustrated for purposes of comparing well known, conventional circular knitting machines to the improvement of the present invention. Only important details of the knitting machines are shown since the construction and operation of circular knitting machines are well known to those skilled in this art. FIGURE 1a shows a typical circular knitting machine of the prior art which is constructed to produce a loop fabric. The machine is of an open top construction and includes vertically disposed needles 10 positioned around the outside of a cylinder member 12. The needles 10 are operated vertically to cooperate with sinkers 14 which are horizontally disposed in a sinker dial member 16. As is conventional in such machines, the sinker dial member 16 is mounted outwardly of the cylinder 12 so as to surround the entire cylinder. As shown in the FIGURES 1b and 10, a loop fabric is produced from two yarns, a first yarn 18 which forms the body of the fabric and a second yarn 20 which forms a loop in the fabric. The body yarn 18 is introduced into a throat portion 22 of the sinker 14 when the sinker is in its outward position, as in FIGURE 1a. Then the sinker is advanced inwardly, as in FIGURE 1b, and a loop yarn 20 is fed into a hook 24 of the needle 10. When the needle 10 is retracted downwardly common needle loops comprising the ground yarn 18 and the loop yarn 20 are formed over the sinker ledge 26, and a so-called sinker loop is formed over a nib 28 of the sinker. As is well known in the prior art, the sinker nib 28 provides for a loop construction in the knitted fabric, and the height of the nib above the sinker ledge 26 determines the level of loop formation in a fabric. With this prior art arrangement, a different loop level is achieved only by replacement with sinker elements 14 with a corresponding height of nibs for forming loops. Of course, this replacement of sinker elements cannot take place while a machine is in operation. Also, it is significant that the single-level loop fabric produced by the apparatus shown in FIGURES 1a through 10 forms all loops on the inside of the tubular fabric which is passing downwardly through the center of the cylinder 12. This makes fabric inspection difiicult during the knitting operation, and it is necessary to turn the fabric inside out before loops can be inspected prior to any subsequent handling or processing of the fabric. FIGURE 1a also illustrates a sinker cam ring 30 on which are fixedly mounted cam means 31 to successively advance and retract sinker elements 14 in synchronized relationship to the up and down movements of needle 10 in a manner Well known in the artw FIGURES 2a through 2e illustrate a modification of the apparatus shown in FIGURES la through 1c. The modification comprises a prior art arrangement to provide a pattern in loop areas which are knitted on the circular knitting machine shown. However, the so-called pattern of loop formation which is attainable from the prior art apparatus shown in FIGURES 2a through 2e is limited to single-level loops placed in selective patterns against areas of ground loops of the fabric itself. The sinker 14 of FIGURE 2a is selectively advanced to a single inner position 35 by a horizontal pattern wheel 32 rotatably mounted on rod member 37. The horizontal pattern wheel 32 has at its outer periphery a series of fins 33 which mesh with butts 15 of sinkers 14'so that the pattern wheel and the sinkers cooperate in a pinion and gear-type relationship. Furthermore, the pattern wheel 32 includes a selective placement of pattern bitts (not shown), and the placement of pattern bitts in the wheel 32 determines which sinkers 14 are to be advanced to an inner position 35. Sinkers which are selected for inward movement by the pattern wheel 32 receive loop yarn over their respective nibs 28, whereas those sinkers which remain in their outward position (as shown in FIGURES 2b through 20) cannot receive loop yarn over their nibs. When the loop yarn is not received over a nib, both the ground yarn and the loop yarn form common loops over the ledge of the unselected sinker. Another arrangement for selectively advancing sinkers with a pattern wheel is illustrated in Agulnek Patent 2,098,446, Nov. 9, 1937. Of course, it can be seen that the loops which are formed with the apparatus which has just been described are of a single level and are formed on the inside of the tubular fabric being knitted in the circular knitting machine. Furthermore, the loop-forming element, i.e., the sinker 14, is positioned at either of two locations relative to the needle, an inner position in which the yarn 20 is formed into a loop over the nib 28, and an outer position in which yarn 20 is formed into a loop together with the ground yarn 18 over sinker ledge 26. Accordingly, the so-called pattern of loop formation is actually a pattern of single-level loops and non-loops as dictated by loop-forming positions of sinkers and inoperative positions of sinkers, respectively.

FIGURE 3 illustrates a vertical section of a portion of a circular knitting machine which is set up to produce tubular loop fabric in accordance with this invention. Basically, the knitting machine inculdes well known cylinder 12 and dial 16 members, and certain details of the cylinder and dial members and other elements associated with a circular knitting machine have been omitted in order to emphasize the improvements of the present invention. It is to be understood that conventional structures and functions of circular knitting machines are included in the machine of this invention. However, certain important changes have been made in the knitting elements associated with such a machine in order to produce the improved results of this invention. In the view of FIGURE 3, the center of the circular knitting machine is toward the left of the figure, and it can be seen that a tubular loop fabric is knitted with all loops on an outside surface of the fabric.

In FIGURE 3, horizontally operable needle elements 40 are radially disposed about a dial member 16 which is positioned inwardly of the cylinder 12. The needle elements 40 are moved inwardly and outwardly by cam means 42 and 44 fixed to a dial cam plate 46 in a well known manner. Individual needle elements 40 cooperate with vertically disposed pattern jacks means 48 which are positioned about the cylinder 12 so as to be operable in vertical directions of movement. The needle elements and pattern jacks are guided in their movements by conventional structures associated with circular knitting machines. The pattern jacks means 48 may comprise elongate strips of metal which are manufactured in accord ance with standards for other jacks which are well known in the textile arts. The pattern jacks 48 of FIGURE 3 are of a special configuration and include an upper yarn engaging portion 50 for forming loops on the outside surface of a tubular fabric which is being knitted. Each pattern jack means 48 has a butt 52 associated with it for a meshing engagement with an angularly disposed rotatably mounted pattern wheel 54. As will be discussed in greater detail below, the pattern wheel 54 may include pattern bitts which dictate positions of vertical placement of individual pattern jack means 48. The pattern jack means 48 which is illustrated in FIGURE 3 functions to cooperate with needle elements 40 to produce a multi-level loop fabric. Different levels of loops can be selectively formed so as to create a patterned effect in the fabric if desired. In order to produce more than one level of loop in a fabric which is being knitted, the upper end 50 of the pattern jack means is provided with yarn engaging surfaces which progressively differ in their depths so as to provide for different levels of loop formations. The construction shown in FIGURE 3 provides for two operating levels of yarn engaging surfaces, and it can be seen that an uppermost surface 56 is a low loopforming surface, while the adjacent surface 57 functions as a high loop-forming surface.

FIGURE 4 diagrammatically illustrates the relationships of the pattern jacks 48 and a pattern wheel 54 to a horizontal plane AA in which the needle elements 40 operate. Also, a conventional cylinder cam means 58 is shown for lifting the pattern jacks 48 to a suitable height for appropriate meshing engagement between the pattern jack butts 52 and the pattern wheel 54. The pattern jacks of FIGURE 4 include the multi-level yarn engaging portions which were just discussed with reference to FIGURE '3. As shown in FIGURE 4, the angularly disposed rotatably mounted, three-position pattern wheel 54 meshes with individual pattern jack means 48 to engage the jack butts 52. This meshing engagement selectively positions the pattern jacks to various levels in accordance with a pattern which has been established in the pattern wheel 54. For example, a low loop-forming level of operation is illustrated for the pattern jacks labelled I and IV; a high loop-forming level is shown by pattern jacks II and III; and a non-loop-forming level is illustrated by the remaining two jacks V and VI. The nonloop-forming level of operation for an individual pattern jack 48 is a result of a pattern jack riding through the pattern wheel 54 in a slot of the wheel which contains no pattern bitt. Such a construction is shown in the sectional view of FIGURE 3 where a pattern jack 48 is illustrated as meshing with an open slot of the pattern wheel 54 without being lifted to a loop-forming level. In the non-loopforming level position, both ground and loop yarns form common needle or ground loops when the dial needle element 40 is urged inwardly by the action of dial cam 42 or 44. FIGURE 3 also illustrates the relative positions of a ground yarn 18 and a loop-forming yarn 20, both of which are fed to the knitting machine in a well known manner to produce loop fabric.

FIGURES 5 and 6 illustrate the same knitting machine and pattern jack constructions which are shown in FIGURE 3, but the pattern jacks 48 are illustrated in different loop-forming levels of operation. In FIGURE 5, the pattern jack 48 is shown in a low, loop-forming level which is dictated by a low bitt 60 contained within one of the slots of the pattern wheel 54. In contrast, FIGURE 6 illustrates a pattern jack 48 in a high-loop position, as dictated by a higher bitt 62 positioned within the pattern wheel 54. Thus, it can be seen that a predetermined arrangement of pattern bitts, and the omission of bitts where desired, will result in a pattern of multi-level loop formations on a knitted fabric. The pattern'wheel 54 is constructed to be easily disassembled by a removal of a top plate 64 so that pattern bitts can be interchanged or removed. High or low pattern bitts can be arranged in successive slots around the periphery of the pattern wheel, and bitts can be omitted where desired to produce only a ground loop stitch. The pattern wheel 54 can then be reassembled for a knitting operation. FIGURES 5 and 6 also illustrate the relationship of ground yarn 18 and loop yarn 20 in the formation of a loop stitch. The loop yarn 20 is introduced into the hook portion 41 of the needle 40 in a position which is outwardly from the yarn engaging surfaces of the pattern jack 48. A ground yarn 18 is introduced inwardly of the pattern jack 48 and on top of a latch 66 associated with the needle element 40. Consequently, as the needle element 40 is cammed inwardly by the dial cams 42 and/or 44, the loop yarn 20 is placed about a yarn engaging surface 56 as seen in FIGURE 5 or surface 57 as illustrated in FIGURE 6. As the needle element 40 continues its inward movement, common loops of both the loop and ground yarns are formed over the combing 68. Since the loop is formed inwardly from an initial outside position, the loop appears in the tubular fabric on the outside, or exposed portion, of the fabric. As already indicated, this feature permits a quick and easy inspection of the fabric while knitting is taking place and without turning the fabric.

FIGURE 7 illustrates a knitting machine which is similar to that shown in FIGURES 3 through 6 with the exception that an alternative form of pattern jack means 48 is provided. The pattern jack means 48 of FIGURE 7 includes a novel configuration for the yarn engaging portion 50 of the pattern jack. The illustrated pattern jack means 48 is useful for forming very precisely controlled configurations for individual loops. The pattern jack is constructed to insure that loops are all of a uniform size and tightness, even when a single-level loop fabric is being knitted. As shown in FIGURE 7, the surfaces 70 and 72 are arranged to initially form a loop on the yarn engaging surface 70, and then to equalize and tighten the loop by a retracting of the pattern jack 48 downwardly through the initially formed loop. The downward movement of the pattern jack 48 causes the larger surface 72 to level the loop to a uniform size and to tighten the loop slightly in the final knitted product. The size of surface 72 has been exaggerated in FIGURE 7 in order to illustrate its function with clarity. However, the actual difference in extent between surfaces 70 and 72 is relatively small but of sufficient dimension to assure equalizing of all loops as the pattern jack means 48 are i'etracted downwardly through the previously formed oops.

FIGURE 8 is an example of a type of pattern effect which may be produced in the practice of the present invention. By a pattern layout of bitts in the pattern wheel 54, portions of a knitted fabric may be made with highloop, low-loop, or no-loop areas, as shown. It will be understood that the illustration of FIGURE 8 is by way of example only, and that attractive effects can also be created by a more random placement of loops. Additionally, it is contempalted that high-loop formations can be sheared without touching low-loop formations so as to produce unusual and interesting random-sheared effects on a loop fabric.

Although the invention has been discussed with reference to particular embodiments, it will be understood that many variations are possible. For example, three levels of loops may be provided by using longer pattern jacks or by lifting individual jacks to higher levels of operation with the pattern wheel and raising cam means 58 of FIGURE 4. In the FIGURE 4 view, all pattern jacks can be extended upwardly so that there is no position in which no loop is formed. Thus, three levels of loops could be formed on the yarn engaging surfaces 56 and 57, and on the jack ledge 74. Alternatively, the pattern wheel can be so set up as to extend the ledge 74 above the plane AA so as to produce a third level of loops when a high bitt 62 is used in the pattern wheel.

Other variations and modifications of the present invention will become apparent to those skilled in this art, and such variations and modifications are intended to be included within the scope of this invention.

What is claimed is:

1. In knitting apparatus for knitting loop fabric on a circular knitting machine of the type having a dial and cylinder construction, the improvement comprising:

needle means radially disposed on a dial means, said needle means being operable in a horizontal plane by cam means associated with the dial means,

vertically disposed pattern jack means arranged around a cylinder of said machine, said pattern jack means having more than one yarn engaging portion to cooperate with said horizontally operable needle means to form knitted loop fabric when body and loop yarns are fed into said machine, each of said pattern jack means having a butt extending outwardly therefrom, and

pattern wheel means associated with said machine and positioned to dictate a pattern of vertical movements for said pattern jack means, said pattern wheel means including means engaging the butt means of said pattern jack means for controlling vertical movements of said pattern jack means, whereby a tubular loop fabric is knitted by said machine with loop formation on an outside surface of the fabric.

2. The improvement of claim 1 wherein said yarn engaging surfaces are of different levels along the longitudinal axis of individual pattern jack means so that different levels of loops are formed in said fabric.

3. The improvement of claim 2 wherein the different levels of a yarn engaging surface are provided along an upper terminal end of individual pattern jack means, said yarn engaging surface progressing from a low loop-forming level to at least one higher loop-forming level.

4. The improvement of claim 3 wherein said progression of the yarn engaging surface is from the uppermost terminal end of an individual pattern jack means toward a lower part of said pattern jack means.

5. The improvement of claim 2 wherein a higher loopforming level of a yarn engaging surface is provided at an uppermost end portion of individual pattern jacks than at lower portions of the same pattern jack means, whereby a loop can be initially formed around a lower portion of an individual pattern jack means and then increased in size as the pattern jack means is withdrawn from the loop being knitted.

6. The improvement of claim 5 wherein all pattern jack means are provided with the same configuration for a yarn engaging surface, whereby loops of greater uniformity can be knitted into a fabric.

7. The improvement of claim 1 wherein said pattern wheel means can be bolted in various vertical positions.

8. The improvement of claim 1 wherein said pattern wheel means has bitt means for dictating vertical movements of said pattern jack means to at last three vertical positions.

9. The improvement of claim 1 wherein means are provided in said pattern Wheel for dictating a plurality of vertical positions for said pattern jack means which include (a) a position wherein a loop yarn does not contact a pattern jack being controlled by said pattern wheel, (b) a position wherein a pattern jack is moved to a position for forming a low-level loop, and (c) a position wherein a pattern jack is moved to a position for forming a high-level loop.

10. The improvement of claim 1 wherein said pattern wheel means is positioned at a single yarn-feeding station.

11. The improvement of claim 10 wherein at least one ground yarn and at least one loop yarn are introduced at said yarn-feeding station.

References Cited UNITED STATES PATENTS 716,767 12/1902 Scott 66-12 727,522 5/1903 Williams 66-9 2,055,598 9/1936 Agulnek 66-50 2,715,824 8/1955 Krauss et a1. 66-93 3,000,199 9/196-1 Felker 66-93 3,241,337 3/1966 Stevens 66-93 3,331,219 7/1967 Brook 66-93 FOREIGN PATENTS 1,273,725 9/1961 France.

9,700 5/ 1908 Great Britain.

WILLIAM C. REYNOLDS, Primary Examiner US. Cl. X.R. 66-9, 92 

